Guess who's been running an NYC prostitution ring...

...An NYPD vice cop, that's who! Okay, a retired New York Police Department vice cop, but still a cop, right?

Ludwig Paz, 51, pulled down more than $2 million a year, according to the NY Post, by running several brothels with the assistance of a few fellow NYPD officers.

Two of his former brothers in blue were given free sex in exchange for letting Ludwig know how close the vice squad might be to busting his operation.

The brothels, in Brooklyn and Queens, were disgusting. One was nothing but a wretched apartment in Brooklyn -- one bedroom complete with box-spring mattress, red ceiling light, and a painting of a man and woman eating dinner.

The Brooklyn brothel's office did include a box of disinfectant wipes, rubbing alcohol and turquoise bra and panties.

The NYPD seized Ludwig on 9-11. Two NYPD officers, a couple of detectives, and three sergeants were arrested the next day on the same charges Ludwig faces: enterprise prostitution, promoting prostitution and official misconduct.

Moreover, this is just the beginning. Sources told the NY Post prosecutors could file charges against another 30 NYPD officers.

The 72-year-old building superintendent for the structure that house the one-bedroom whore house said he had no idea what was going on inside the apartment at 880 Gates Avenue, Bensonhurst, Brooklyn.

However, William Burgess told the Post he knew something was amiss.

"I saw a lot of gentlemen always coming in and out of here,” said William, adding that business appeared to begin at noon and run through the night.

“I see people coming in and out of the building — the noise at night always bothered me: bam, bam, bam."

Then again, William knows how to mind his own knitting.

"People have freedom here," he said. "As long as there is no violence or piss in my hallway, I don’t care what you do.”

Wicked Justice: Book 3 From the St. Isidore Collection is available wherever books are sold including the Crime Stories Book Store and Amazon/Kindle.